10 Hp 4 stoke on an 18' lapstake runabout

[georgel]

I would like to put a 10 hp on my 1960 Chetek glued plywood lapstrake runabout. Is this engine suitable. The boat weighs around 800# and is similar to a Thompson of that vintge. Also a question about "hithrust" is this just a prop. or does it involve different gearing and prop clearance as in a Yammi.?
Georgel

 

[hondadude]

It seems a bit small for that boat. Seeing some others on the net, it looks like many of them have around a 40 hp on them.

The 10 HP will push the boat, but it will not get up on plane. The hi thrust is just a prop. Normally, it is about a 10 x7 pitch. We usually put them on 10hp when they are used for kicker motors on fishing boats or larger boats like yours or even small pontoon boats.

If you boat in waters with a lot of current, tides or heavy wind, you might be disappointed. If you are boating in a lake and not is a hurry, it would be ok.

Others may have some better estimates, but you probably will not see 10mph in speed.

The key is to make sure it has the correct prop so it can reach proper max rpm.

Mike

 

[jgmo]

Mike pretty much covered it. I will add that your 800lb. hull becomes a 1200 to 1400 lb. vessel after being loaded with two humans, fishing gear and a cooler full of beer and THEN, you add the weight of the motor it'self and 10 hp will only be adequate for trolling.